Presented on Feb 21, 2013 as part of a springsource.org webinar. A video of the presentation will be available 2 weeks later at http://www.youtube.com/springsourcedev.

1. Testing Web Applications with Spring 3.2
Sam Brannen, Swiftmind, @sam_brannen
Rossen Stoyanchev, VMware, @rstoya05
© 2012 SpringSource, by VMware. All rights reserved

2. Today's Speakers
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3. Sam Brannen
 Spring and Java Consultant @ Swiftmind
 Developing Java for over 15 years
 Spring Framework Core Committer since 2007
 Spring Trainer
 Presenter on Spring, Java, OSGi, and testing
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4. Rossen Stoyanchev
 Spring Framework core committer
 Focus on Spring Web
 Main developer of Spring MVC Test
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5. Agenda
 Spring TestContext Framework Updates
 Spring MVC Test Framework
 Q&A
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6. Spring TestContext Framework Updates
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7. What's New in the Spring TCF?
 Upgraded to JUnit 4.11 and TestNG 6.5.2
 Loading WebApplicationContexts
 Testing request- and session-scoped beans
 Support for ApplicationContextInitializers
 Loading context hierarchies (3.2.1)
 And more… (see presentation from SpringOne 2GX 2012)
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8. Loading a WebApplicationContext
Q: How do you tell the TestContext Framework to load a
WebApplicationContext?
A: Just annotate your test class with @WebAppConfiguration!
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9. @WebAppConfiguration
 Denotes that the context should be a WebApplicationContext
 Configures the resource path for the web app
• Used by MockServletContext
• Defaults to “src/main/webapp”
• Paths are file-system folders, relative to the project root not classpath resources
• The classpath: prefix is also supported
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10. Example: @WebAppConfiguration
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11. Example: @WebAppConfiguration
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12. Example: @WebAppConfiguration
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13. ServletTestExecutionListener
 Sets up default thread-local state via RequestContextHolder before
each test method
 Creates:
• MockHttpServletRequest
• MockHttpServletResponse
• ServletWebRequest
 Ensures that the MockHttpServletResponse and ServletWebRequest
can be injected into the test instance
 Cleans up thread-local state after each test method
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14. Example: Injecting Mocks
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15. Web Scopes – Review
 request: lifecycle tied to the current HttpServletRequest
 session: lifecycle tied to the current HttpSession
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16. Example: Request-scoped Bean Test
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17. Example: Request-scoped Bean Config
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18. Example: Session-scoped Bean Test
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19. Example: Session-scoped Bean Config
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20. ApplicationContextInitializer
 Introduced in Spring 3.1
 Used for programmatic initialization of a
ConfigurableApplicationContext
 For example:
• to register property sources
• to activate profiles against the Environment
 Configured in web.xml by specifying contextInitializerClasses via
• context-param for the ContextLoaderListener
• init-param for the DispatcherServlet
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21. Example: Multiple Initializers
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22. Using Initializers in Tests
 Configured in @ContextConfiguration via the initializers attribute
 Inheritance can be controlled via the inheritInitializers attribute
 An ApplicationContextInitializer may configure the entire context
• XML resource locations or annotated classes are no longer required
 Initializers are now part of the context cache key
 Initializers are ordered based on Spring's Ordered interface or the
@Order annotation
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23. Application Context Hierarchies
 Currently only flat, non-hierarchical contexts are supported in tests.
 There’s no easy way to create contexts with parent-child
relationships.
 But… hierarchies are supported in production.
 Wouldn’t it be nice if you could test them, too?!
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24. Testing Context Hierarchies in version 3.2.2 (!)
 New @ContextHierarchy annotation
• used in conjunction with @ContextConfiguration
 @ContextConfiguration now supports a ‘name’ attribute
• for merging and overriding hierarchy configuration
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25. Single Test with Context Hierarchy
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26. Class and Context Hierarchies
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27. Built-in Spring MVC Test Support
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28. Overview
 Dedicated support for testing Spring MVC applications
 Fluent API
 Very easy to write
 Includes client and server-side support
 Servlet container not required
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29. In More Detail
 Included in spring-test module of Spring Framework 3.2
 Builds on
• TestContext framework for loading Spring MVC configuration
• MockHttpServletRequest/Response and other “mock” types
 Server-side tests involve DispatcherServlet
 Client-side REST testing for code using RestTemplate
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30. Spring MVC Test History
 Evolved as independent project on Github
• https://github.com/SpringSource/spring-test-mvc
 Now folded into Spring Framework 3.2
 Former project still supports Spring Framework 3.1
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31. Server-Side Example
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32. A Note On Fluent API Usage
 Requires static imports
import static MockMvcRequestBuilders.get;
import static MockMvcResultMatchers.status;
mockMvc.perform(get(“/foo”)).andExpect(status().isOk())
 Add as “favorite static members” in Eclipse preferences
• Java -> Editor -> Content Assist -> Favorites
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33. Server-Side Test Recap
 Actual Spring MVC configuration loaded
 MockHttpServletRequest prepared
 Executed via DispatcherServlet
 Assertions applied on the resulting MockHttpServletResponse
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34. Integration Or Unit Testing?
 Mock request/response types, no Servlet container
 However..
• DispatcherServlet + actual Spring MVC configuration used
 Hence..
• Not full end-to-end testing, i.e. does not replace Selenium
• However provides full confidence in Spring MVC web layer
 In short, integration testing for Spring MVC
• Don't get too caught up in terminology!
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35. Strategy For Testing
 Focus on testing the Spring MVC web layer alone
• Inject controllers with mock services or database repositories
 Thoroughly test Spring MVC
• Including code and configuration
 Separate from lower layer integration tests
• E.g. database tests
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36. Declaring A Mock Dependency
 Since we're loading actual Spring MVC config
 Need to declare mock dependencies
<bean class="org.mockito.Mockito" factory-method="mock">
<constructor-arg value="org.example.FooDao"/>
</bean>
 Then simply inject the mock instance into the test class
• Via @Autowired
• Set up and reset via @Before, @Test, and @After methods
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37. What Can Be Tested?
 Response status, headers, and content
• Focus on asserting these first...
 Spring MVC and Servlet specific results
• Model, flash, session, request attributes
• Mapped controller method and interceptors
• Resolved exceptions
 Various options for asserting the response body
• JSONPath, XPath, XMLUnit
• Hamcrest matchers
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38. What About the View Layer?
 All view templating technologies will work
• Freemarker/Velocity, Thymeleaf, JSON, XML, PDF, etc.
 Except for JSPs (no Servlet container!)
• You can however assert the selected JSP
 No redirecting and forwarding
• You can however assert the redirected or forwarded URL
 Also of interest
• HTML Unit / Selenium Driver integration (experimental)
• https://github.com/SpringSource/spring-test-mvc-htmlunit
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39. Useful Option For Debugging
 Print all details to the console, i.e. System.out
mockMvc.perform("/foo")
.andDo(print())
.andExpect(status().Ok())
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40. “Standalone” Setup
 No Spring configuration is loaded
 Test one controller at a time
 Just provide the controller instance
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41. “Standalone” Setup Example
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42. Tests with Servlet Filters
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43. Re-use Request Properties and Expectations
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44. Direct Access to the Underlying MvcResult
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45. Client-Side REST Example
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46. Client-Side REST Test Recap
 An instance of RestTemplate configured with custom
ClientHttpRequestFactory
 Records and asserts expected requests
• Instead of executing them
 Code using RestTemlpate can now be invoked
 Use verify() to assert all expectations were executed
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47. Acknowledgements
The Spring MVC Test support draws
inspiration from similar test framework in
Spring Web Services
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48. Further Resources: Spring MVC Test
 Reference doc chapter on Spring MVC Test
 Sample tests in the framework source code
• https://github.com/SpringSource/spring-framework/tree/3.2.x/spring-test-
mvc/src/test/java/org/springframework/test/web/servlet/samples
• https://github.com/SpringSource/spring-framework/tree/3.2.x/spring-test-
mvc/src/test/java/org/springframework/test/web/client/samples
 Tests in spring-mvc-showcase
• https://github.com/SpringSource/spring-mvc-showcase
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49. Further Resources Cont'd
 Spring Framework
• http://www.springsource.org/spring-framework
• Reference manual and Javadoc
 Forums
• http://forum.springframework.org
 JIRA
• http://jira.springframework.org
 GitHub
• https://github.com/SpringSource/spring-framework
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50. Blogs
 SpringSource Team Blog
• http://blog.springsource.com/
 Swiftmind Team Blog
• http://www.swiftmind.com/blog/
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51. Q&A
 Sam Brannen
• twitter: @sam_brannen
• www.slideshare.net/sbrannen
• www.swiftmind.com
 Rossen Stoyanchev
• twitter: @rstoya05
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